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<head>
	<title>Gmail API Quickstart</title>
	<meta charset='utf-8' />
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<p>Gmail API Quickstart</p>

<!--Add buttons to initiate auth sequence and sign out-->
<button id="authorize-button" style="display: none;">Authorize</button>
<button id="signout-button" style="display: none;">Sign Out</button>

<pre id="content"></pre>

<script type="text/javascript">
    // Client ID and API key from the Developer Console
    var CLIENT_ID = '319757543751-bj4lvlrthqal00u80r3dqfqm0i61f5g1.apps.googleusercontent.com';

    // Array of API discovery doc URLs for APIs used by the quickstart
    var DISCOVERY_DOCS = ["https://www.googleapis.com/discovery/v1/apis/gmail/v1/rest"];

    // Authorization scopes required by the API; multiple scopes can be
    // included, separated by spaces.
    var SCOPES = 'https://www.googleapis.com/auth/gmail.readonly';

    var authorizeButton = document.getElementById('authorize-button');
    var signoutButton = document.getElementById('signout-button');

    /**
     *  On load, called to load the auth2 library and API client library.
     */
    function handleClientLoad() {
        gapi.load('client:auth2', initClient);
    }

    /**
     *  Initializes the API client library and sets up sign-in state
     *  listeners.
     */
    function initClient() {
        gapi.client.init({
            discoveryDocs: DISCOVERY_DOCS,
            clientId: CLIENT_ID,
            scope: SCOPES
        }).then(function () {
            // Listen for sign-in state changes.
            gapi.auth2.getAuthInstance().isSignedIn.listen(updateSigninStatus);

            // Handle the initial sign-in state.
            updateSigninStatus(gapi.auth2.getAuthInstance().isSignedIn.get());
            authorizeButton.onclick = handleAuthClick;
            signoutButton.onclick = handleSignoutClick;
        });
    }

    /**
     *  Called when the signed in status changes, to update the UI
     *  appropriately. After a sign-in, the API is called.
     */
    function updateSigninStatus(isSignedIn) {
        if (isSignedIn) {
            authorizeButton.style.display = 'none';
            signoutButton.style.display = 'block';
            listLabels();
        } else {
            authorizeButton.style.display = 'block';
            signoutButton.style.display = 'none';
        }
    }

    /**
     *  Sign in the user upon button click.
     */
    function handleAuthClick(event) {
        gapi.auth2.getAuthInstance().signIn();
    }

    /**
     *  Sign out the user upon button click.
     */
    function handleSignoutClick(event) {
        gapi.auth2.getAuthInstance().signOut();
    }

    /**
     * Append a pre element to the body containing the given message
     * as its text node. Used to display the results of the API call.
     *
     * @param {string} message Text to be placed in pre element.
     */
    function appendPre(message) {
        var pre = document.getElementById('content');
        var textContent = document.createTextNode(message + '\n');
        pre.appendChild(textContent);
    }

    /**
     * Print all Labels in the authorized user's inbox. If no labels
     * are found an appropriate message is printed.
     */
    function listLabels() {
        gapi.client.gmail.users.labels.list({
            'userId': 'me'
        }).then(function(response) {
            var labels = response.result.labels;
            appendPre('Labels:');

            if (labels && labels.length > 0) {
                for (i = 0; i < labels.length; i++) {
                    var label = labels[i];
                    appendPre(label.name)
                }
            } else {
                appendPre('No Labels found.');
            }
        });
    }
    function lisMessage() {
        gapi.client.gmail.users.labels.list({
            'userId': 'me'
        }).then(function(response) {
            var labels = response.result.labels;
            appendPre('Labels:');

            if (labels && labels.length > 0) {
                for (i = 0; i < labels.length; i++) {
                    var label = labels[i];
                    appendPre(label.name)
                }
            } else {
                appendPre('No Labels found.');
            }
        });
    }
</script>

<script async defer src="https://apis.google.com/js/api.js"
		onload="this.onload=function(){};handleClientLoad()"
		onreadystatechange="if (this.readyState === 'complete') this.onload()">
</script>
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